The cephalosporin (6R,7R)-3-[(5-amino-4-{[(2-aminoethyl)carbamoyl]amino}-1-methyl-1-pyrazol-2-ium-2-yl)methyl]-7-{(2Z)-2-(5-amino-1,2,4-thiadiazol-3-yl)-2-[(1-carboxy-1-methylethoxy)imino]acetyl}amino)-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylate (also referred to as “ceftolozane”) is an antibacterial agent. The antibacterial activity of ceftolozane is believed to result from its interaction with penicillin binding proteins (PBPs) to inhibit the biosynthesis of the bacterial cell wall which acts to stop bacterial replication.
Ceftolozane can be combined (e.g., mixed) with β-lactamase inhibitor (“BLI”), such as tazobactam. Tazobactam is a BLI against Class A and some Class C β-lactamases, with well-established in vitro and in vivo efficacy in combination with active β-lactam antibiotics. The combination of ceftolozane, or a pharmaceutically acceptable salt thereof and tazobactam or a pharmaceutically acceptable salt thereof in an amount providing a 2:1 weight ratio between the amount of ceftolozane active and tazobactam active is an antibiotic pharmaceutical composition (“CXA-201”) formulated for parenteral administration. CXA-201 displays potent antibacterial activity in vitro against common Gram-negative and selected Gram-positive organisms that cause complicated intra-abdominal infections or complicated urinary tract infections. Moreover, CXA-201 has demonstrated efficacy in clinical trials against these infections (See, e.g., Examples 3-5), and the recommended dosage for patients with normal kidney function [creatinine clearance (CrCL)>50 mL/min] is 1.5 grams of CXA-201 (1 g ceftolozane active/500 mg tazobactam active) administered intravenously over one hour every eight hours (See Table 1 below).
TABLE 1Dosage of CXA-201 by Infection in Patientswith Creatinine Clearance (CrCL) >50 mL/minDoseInfusionCXA-TimeDuration ofInfection201Frequency(hours)TreatmentComplicated Intra-1.5 gEvery 814-14daysAbdominal InfectionsHoursComplicated Urinary1.5 gEvery 817daysTract Infections,HoursincludingPyelonephritis
The intravenous formulation of CXA-201 can be prepared by reconstituting a fixed dose combination mixture of two active components (ceftolozane and tazobactam), and intravenously administering the reconstituted pharmaceutical composition. The pharmacokinetic (PK) profile of ceftolozane/tazobactam has been studied in several preclinical and clinical studies. In healthy volunteers the PK of ceftolozane/tazobactam is dose-proportional and linear across a wide range of doses (up to 3000 mg/1500 mg as a single dose) with a terminal elimination half-life (t½β) of approximately 2.5 hours for ceftolozane and 1 hour for tazobactam. Both ceftolozane and tazobactam are primarily excreted in the urine; ceftolozane almost completely in the urine as unchanged parent drug suggesting minimal metabolism, and tazobactam with 80% as the unchanged parent drug and the remaining as inactive M1 metabolite that is formed via hydrolysis of tazobactam (See, e.g., Miller B, Hershberger E, Benziger D, Trinh M, Friedland I., “Pharmacokinetics and safety of intravenous ceftolozane-tazobactam in healthy adult subjects following single and multiple ascending doses,” Antimicrob Agents Chemother. 2012; 56(6):3086-3091).
Ceftolozane is eliminated through the kidney. Example 7 provides the pharmacokinetics 0.5 of ceftolozane/tazobactam in healthy volunteers. In healthy volunteers the PK of ceftolozane/tazobactam is dose-proportional and linear across a wide range of doses (up to 3000 mg/1500 mg as a single dose) with a terminal elimination half-life (t1/2β) of approximately 2.5 hours for ceftolozane and 1 hour for tazobactam. Both ceftolozane and tazobactam are primarily excreted in the urine; ceftolozane almost completely in the urine as unchanged parent drug suggesting minimal metabolism, and tazobactam with 80% as the unchanged parent drug and the remaining as inactive M1 metabolite that is formed via hydrolysis of tazobactam. There is no drug-drug interaction between ceftolozane and tazobactam when co-administered.
However, impaired kidney function can result in slower drug clearance of ceftolozane and in increased plasma drug levels. Accordingly, the dosing of CXA-201 in Table 1 is not appropriate for certain patients with advanced renal impairment (including, for example, patients with creatinine clearance less than about 50 mL/minute, such as patients with moderate to severe renal disease or patients in end stage renal disease who are undergoing hemodialysis). Therefore, there remains a medical need for determining appropriate dosing adjustments for safely and effectively administering a CXA-201 product to a patient at various stages of renal function impairment, including treatment of patients with end stage renal disease (ESRD) (e.g., patients having a creatinine clearance of less than 15 mL/min).
Adjustments in methods of administering other parenteral anti-infective therapies to patients with impaired renal function do not adequately address the unmet medical need for determining safe and effective methods of administering ceftolozane/tazobactam to patients with renal impairment. Modifications in the manner of administering parenteral anti-infective therapies to treat patients with impaired renal function include changes in the dose amount and/or dose interval (including products disclosed, e.g., in FIG. 28). For example, modifications in the parenteral administration of a pharmaceutical composition to patients with impaired renal function can include (1) decreasing the individual dose and increasing the time between doses (e.g., administering 2.25 g of piperacillin/tazobactam every 8 or 12 hours with an additional 0.75 g following dialysis, instead of 3.375 g administered every 6 hours, for treating indicated infections other than nosocomial pneumonia), (2) increasing the time between doses (e.g., administering 1 g of cefepime hydrochloride on day 1 followed by 500 mg every 24 hours thereafter, instead of 0.5-1 or 2 g administered every 12 hours, for urinary tract or intra-abdominal infections), (3) decreasing the amount of individual doses without changing the time between doses (e.g., administering 200 mg of ceftaroline fasamil every 12 hours, instead of 600 mg administered every 12 hours, for certain skin infections or pneumonia), and (4) not changing the dose amount or time between doses (e.g., when administering intravenous linezolid or ceftriaxone sodium to a patient with renal impairment).
There remains a need for safe and effective methods of administering a CXA-201 anti-infective product to patients having various levels of renal impairment as characterized by reduced creatinine clearance (CrCl).